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<div class="title">simple_pooled_pg.py</div>  </div>
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<a href="simple__pooled__pg_8py.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"><a class="line" href="namespaceaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg.html">    1</a></span>&#160;<span class="stringliteral">&quot;&quot;&quot;SimplePooledPg - a very simple classic PyGreSQL connection pool.</span></div>
<div class="line"><a name="l00002"></a><span class="lineno">    2</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00003"></a><span class="lineno">    3</span>&#160;<span class="stringliteral">Implements a pool of threadsafe cached connections</span></div>
<div class="line"><a name="l00004"></a><span class="lineno">    4</span>&#160;<span class="stringliteral">to a PostgreSQL database which are transparently reused,</span></div>
<div class="line"><a name="l00005"></a><span class="lineno">    5</span>&#160;<span class="stringliteral">using the classic (not DB-API 2 compliant) PyGreSQL pg API.</span></div>
<div class="line"><a name="l00006"></a><span class="lineno">    6</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00007"></a><span class="lineno">    7</span>&#160;<span class="stringliteral">This should result in a speedup for persistent applications</span></div>
<div class="line"><a name="l00008"></a><span class="lineno">    8</span>&#160;<span class="stringliteral">such as the &quot;Webware for Python&quot; AppServer.</span></div>
<div class="line"><a name="l00009"></a><span class="lineno">    9</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00010"></a><span class="lineno">   10</span>&#160;<span class="stringliteral">For more information on PostgreSQL, see:</span></div>
<div class="line"><a name="l00011"></a><span class="lineno">   11</span>&#160;<span class="stringliteral">    https://www.postgresql.org/</span></div>
<div class="line"><a name="l00012"></a><span class="lineno">   12</span>&#160;<span class="stringliteral">For more information on PyGreSQL, see:</span></div>
<div class="line"><a name="l00013"></a><span class="lineno">   13</span>&#160;<span class="stringliteral">    http://www.pygresql.org</span></div>
<div class="line"><a name="l00014"></a><span class="lineno">   14</span>&#160;<span class="stringliteral">For more information on Webware for Python, see:</span></div>
<div class="line"><a name="l00015"></a><span class="lineno">   15</span>&#160;<span class="stringliteral">    https://webwareforpython.github.io/w4py/</span></div>
<div class="line"><a name="l00016"></a><span class="lineno">   16</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00017"></a><span class="lineno">   17</span>&#160;<span class="stringliteral">Measures are taken to make the pool of connections threadsafe</span></div>
<div class="line"><a name="l00018"></a><span class="lineno">   18</span>&#160;<span class="stringliteral">regardless of the fact that the PyGreSQL pg module itself is</span></div>
<div class="line"><a name="l00019"></a><span class="lineno">   19</span>&#160;<span class="stringliteral">not threadsafe at the connection level.  Connections will never be</span></div>
<div class="line"><a name="l00020"></a><span class="lineno">   20</span>&#160;<span class="stringliteral">shared between threads, so you can safely use transactions.</span></div>
<div class="line"><a name="l00021"></a><span class="lineno">   21</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00022"></a><span class="lineno">   22</span>&#160;<span class="stringliteral">Usage:</span></div>
<div class="line"><a name="l00023"></a><span class="lineno">   23</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00024"></a><span class="lineno">   24</span>&#160;<span class="stringliteral">The idea behind SimplePooledPg is that it&#39;s completely transparent.</span></div>
<div class="line"><a name="l00025"></a><span class="lineno">   25</span>&#160;<span class="stringliteral">After you have established your connection pool, stating the</span></div>
<div class="line"><a name="l00026"></a><span class="lineno">   26</span>&#160;<span class="stringliteral">number of connections to be cached in the pool and the</span></div>
<div class="line"><a name="l00027"></a><span class="lineno">   27</span>&#160;<span class="stringliteral">connection parameters, e.g.</span></div>
<div class="line"><a name="l00028"></a><span class="lineno">   28</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160;<span class="stringliteral">    from dbutils.simple_pooled_pg import PooledPg</span></div>
<div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;<span class="stringliteral">    dbpool = PooledPg(5, host=..., database=..., user=..., ...)</span></div>
<div class="line"><a name="l00031"></a><span class="lineno">   31</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00032"></a><span class="lineno">   32</span>&#160;<span class="stringliteral">you can demand database connections from that pool,</span></div>
<div class="line"><a name="l00033"></a><span class="lineno">   33</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00034"></a><span class="lineno">   34</span>&#160;<span class="stringliteral">    db = dbpool.connection()</span></div>
<div class="line"><a name="l00035"></a><span class="lineno">   35</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00036"></a><span class="lineno">   36</span>&#160;<span class="stringliteral">and use them just as if they were ordinary PyGreSQL pg API</span></div>
<div class="line"><a name="l00037"></a><span class="lineno">   37</span>&#160;<span class="stringliteral">connections.  It&#39;s really just a proxy class.</span></div>
<div class="line"><a name="l00038"></a><span class="lineno">   38</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00039"></a><span class="lineno">   39</span>&#160;<span class="stringliteral">db.close() will return the connection to the pool, it will not</span></div>
<div class="line"><a name="l00040"></a><span class="lineno">   40</span>&#160;<span class="stringliteral">actually close it.  This is so your existing code works nicely.</span></div>
<div class="line"><a name="l00041"></a><span class="lineno">   41</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;<span class="stringliteral">Ideas for improvement:</span></div>
<div class="line"><a name="l00043"></a><span class="lineno">   43</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00044"></a><span class="lineno">   44</span>&#160;<span class="stringliteral">* Do not create the maximum number of connections on startup</span></div>
<div class="line"><a name="l00045"></a><span class="lineno">   45</span>&#160;<span class="stringliteral">already, but only a certain number and the rest on demand.</span></div>
<div class="line"><a name="l00046"></a><span class="lineno">   46</span>&#160;<span class="stringliteral">* Detect and transparently reset &quot;bad&quot; connections.  The PyGreSQL</span></div>
<div class="line"><a name="l00047"></a><span class="lineno">   47</span>&#160;<span class="stringliteral">pg API provides a status attribute and a reset() method for that.</span></div>
<div class="line"><a name="l00048"></a><span class="lineno">   48</span>&#160;<span class="stringliteral">* Connections should have some sort of &quot;maximum usage limit&quot;</span></div>
<div class="line"><a name="l00049"></a><span class="lineno">   49</span>&#160;<span class="stringliteral">after which they should be automatically closed and reopened.</span></div>
<div class="line"><a name="l00050"></a><span class="lineno">   50</span>&#160;<span class="stringliteral">* Prefer or enforce thread affinity for the connections.</span></div>
<div class="line"><a name="l00051"></a><span class="lineno">   51</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00052"></a><span class="lineno">   52</span>&#160;<span class="stringliteral">Please note that these and other ideas have been already</span></div>
<div class="line"><a name="l00053"></a><span class="lineno">   53</span>&#160;<span class="stringliteral">implemented in in PooledPg, a more sophisticated version</span></div>
<div class="line"><a name="l00054"></a><span class="lineno">   54</span>&#160;<span class="stringliteral">of SimplePooledPg.  You might also consider using PersistentPg</span></div>
<div class="line"><a name="l00055"></a><span class="lineno">   55</span>&#160;<span class="stringliteral">instead for thread-affine persistent PyGreSQL connections.</span></div>
<div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;<span class="stringliteral">SimplePooledPg may still serve as a very simple reference</span></div>
<div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;<span class="stringliteral">and example implementation for developers.</span></div>
<div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00060"></a><span class="lineno">   60</span>&#160;<span class="stringliteral">Copyright, credits and license:</span></div>
<div class="line"><a name="l00061"></a><span class="lineno">   61</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00062"></a><span class="lineno">   62</span>&#160;<span class="stringliteral">* Contributed as supplement for Webware for Python and PyGreSQL</span></div>
<div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;<span class="stringliteral">  by Christoph Zwerschke in September 2005</span></div>
<div class="line"><a name="l00064"></a><span class="lineno">   64</span>&#160;<span class="stringliteral">* Based on the code of DBPool, contributed to Webware for Python</span></div>
<div class="line"><a name="l00065"></a><span class="lineno">   65</span>&#160;<span class="stringliteral">  by Dan Green in December 2000</span></div>
<div class="line"><a name="l00066"></a><span class="lineno">   66</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00067"></a><span class="lineno">   67</span>&#160;<span class="stringliteral">Licensed under the MIT license.</span></div>
<div class="line"><a name="l00068"></a><span class="lineno">   68</span>&#160;<span class="stringliteral">&quot;&quot;&quot;</span></div>
<div class="line"><a name="l00069"></a><span class="lineno">   69</span>&#160; </div>
<div class="line"><a name="l00070"></a><span class="lineno">   70</span>&#160;<span class="keyword">from</span> pg <span class="keyword">import</span> DB <span class="keyword">as</span> PgConnection</div>
<div class="line"><a name="l00071"></a><span class="lineno">   71</span>&#160; </div>
<div class="line"><a name="l00072"></a><span class="lineno">   72</span>&#160;<span class="keyword">from</span> . <span class="keyword">import</span> __version__</div>
<div class="line"><a name="l00073"></a><span class="lineno">   73</span>&#160; </div>
<div class="line"><a name="l00074"></a><span class="lineno">   74</span>&#160; </div>
<div class="line"><a name="l00075"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html">   75</a></span>&#160;<span class="keyword">class </span><a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html">PooledPgConnection</a>:</div>
<div class="line"><a name="l00076"></a><span class="lineno">   76</span>&#160;    <span class="stringliteral">&quot;&quot;&quot;A proxy class for pooled PostgreSQL connections.</span></div>
<div class="line"><a name="l00077"></a><span class="lineno">   77</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00078"></a><span class="lineno">   78</span>&#160;<span class="stringliteral">    You don&#39;t normally deal with this class directly,</span></div>
<div class="line"><a name="l00079"></a><span class="lineno">   79</span>&#160;<span class="stringliteral">    but use PooledPg to get new connections.</span></div>
<div class="line"><a name="l00080"></a><span class="lineno">   80</span>&#160;<span class="stringliteral">    &quot;&quot;&quot;</span></div>
<div class="line"><a name="l00081"></a><span class="lineno">   81</span>&#160; </div>
<div class="line"><a name="l00082"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a1dc29b18e0b02d3f4ad84bc543f75d05">   82</a></span>&#160;    <span class="keyword">def </span><a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a1dc29b18e0b02d3f4ad84bc543f75d05">__init__</a>(self, pool, con):</div>
<div class="line"><a name="l00083"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#aa6e8fb5dc582c2d9b4243cadcf40f8f8">   83</a></span>&#160;        self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#aa6e8fb5dc582c2d9b4243cadcf40f8f8">_con</a> = con</div>
<div class="line"><a name="l00084"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a53256f6e73bf8a755c26c21d9406c7be">   84</a></span>&#160;        self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a53256f6e73bf8a755c26c21d9406c7be">_pool</a> = pool</div>
<div class="line"><a name="l00085"></a><span class="lineno">   85</span>&#160; </div>
<div class="line"><a name="l00086"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a1961b0971acfb8564d8f3d65c5ec5bac">   86</a></span>&#160;    <span class="keyword">def </span><a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a1961b0971acfb8564d8f3d65c5ec5bac">close</a>(self):</div>
<div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;        <span class="stringliteral">&quot;&quot;&quot;Close the pooled connection.&quot;&quot;&quot;</span></div>
<div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;        <span class="comment"># Instead of actually closing the connection,</span></div>
<div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160;        <span class="comment"># return it to the pool so it can be reused.</span></div>
<div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160;        <span class="keywordflow">if</span> self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#aa6e8fb5dc582c2d9b4243cadcf40f8f8">_con</a> <span class="keywordflow">is</span> <span class="keywordflow">not</span> <span class="keywordtype">None</span>:</div>
<div class="line"><a name="l00091"></a><span class="lineno">   91</span>&#160;            self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a53256f6e73bf8a755c26c21d9406c7be">_pool</a>.cache(self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#aa6e8fb5dc582c2d9b4243cadcf40f8f8">_con</a>)</div>
<div class="line"><a name="l00092"></a><span class="lineno">   92</span>&#160;            self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#aa6e8fb5dc582c2d9b4243cadcf40f8f8">_con</a> = <span class="keywordtype">None</span></div>
<div class="line"><a name="l00093"></a><span class="lineno">   93</span>&#160; </div>
<div class="line"><a name="l00094"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a58d4f64fbdb7c5c56b498a1c1062154f">   94</a></span>&#160;    <span class="keyword">def </span><a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a58d4f64fbdb7c5c56b498a1c1062154f">__getattr__</a>(self, name):</div>
<div class="line"><a name="l00095"></a><span class="lineno">   95</span>&#160;        <span class="comment"># All other members are the same.</span></div>
<div class="line"><a name="l00096"></a><span class="lineno">   96</span>&#160;        <span class="keywordflow">return</span> getattr(self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#aa6e8fb5dc582c2d9b4243cadcf40f8f8">_con</a>, name)</div>
<div class="line"><a name="l00097"></a><span class="lineno">   97</span>&#160; </div>
<div class="line"><a name="l00098"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#ade325c32687db9b48d41911b9d03d7fd">   98</a></span>&#160;    <span class="keyword">def </span><a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#ade325c32687db9b48d41911b9d03d7fd">__del__</a>(self):</div>
<div class="line"><a name="l00099"></a><span class="lineno">   99</span>&#160;        self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a1961b0971acfb8564d8f3d65c5ec5bac">close</a>()</div>
<div class="line"><a name="l00100"></a><span class="lineno">  100</span>&#160; </div>
<div class="line"><a name="l00101"></a><span class="lineno">  101</span>&#160; </div>
<div class="line"><a name="l00102"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html">  102</a></span>&#160;<span class="keyword">class </span><a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html">PooledPg</a>:</div>
<div class="line"><a name="l00103"></a><span class="lineno">  103</span>&#160;    <span class="stringliteral">&quot;&quot;&quot;A very simple PostgreSQL connection pool.</span></div>
<div class="line"><a name="l00104"></a><span class="lineno">  104</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00105"></a><span class="lineno">  105</span>&#160;<span class="stringliteral">    After you have created the connection pool,</span></div>
<div class="line"><a name="l00106"></a><span class="lineno">  106</span>&#160;<span class="stringliteral">    you can get connections using getConnection().</span></div>
<div class="line"><a name="l00107"></a><span class="lineno">  107</span>&#160;<span class="stringliteral">    &quot;&quot;&quot;</span></div>
<div class="line"><a name="l00108"></a><span class="lineno">  108</span>&#160; </div>
<div class="line"><a name="l00109"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a50172a1bcf52208970d30d27859554a6">  109</a></span>&#160;    version = __version__</div>
<div class="line"><a name="l00110"></a><span class="lineno">  110</span>&#160; </div>
<div class="line"><a name="l00111"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#ae03edf57ff55310069135c2e77b19dee">  111</a></span>&#160;    <span class="keyword">def </span><a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#ae03edf57ff55310069135c2e77b19dee">__init__</a>(self, maxconnections, *args, **kwargs):</div>
<div class="line"><a name="l00112"></a><span class="lineno">  112</span>&#160;        <span class="stringliteral">&quot;&quot;&quot;Set up the PostgreSQL connection pool.</span></div>
<div class="line"><a name="l00113"></a><span class="lineno">  113</span>&#160;<span class="stringliteral"></span> </div>
<div class="line"><a name="l00114"></a><span class="lineno">  114</span>&#160;<span class="stringliteral">        maxconnections: the number of connections cached in the pool</span></div>
<div class="line"><a name="l00115"></a><span class="lineno">  115</span>&#160;<span class="stringliteral">        args, kwargs: the parameters that shall be used to establish</span></div>
<div class="line"><a name="l00116"></a><span class="lineno">  116</span>&#160;<span class="stringliteral">            the PostgreSQL connections using pg.connect()</span></div>
<div class="line"><a name="l00117"></a><span class="lineno">  117</span>&#160;<span class="stringliteral">        &quot;&quot;&quot;</span></div>
<div class="line"><a name="l00118"></a><span class="lineno">  118</span>&#160;        <span class="comment"># Since there is no connection level safety, we</span></div>
<div class="line"><a name="l00119"></a><span class="lineno">  119</span>&#160;        <span class="comment"># build the pool using the synchronized queue class</span></div>
<div class="line"><a name="l00120"></a><span class="lineno">  120</span>&#160;        <span class="comment"># that implements all the required locking semantics.</span></div>
<div class="line"><a name="l00121"></a><span class="lineno">  121</span>&#160;        <span class="keywordflow">try</span>:</div>
<div class="line"><a name="l00122"></a><span class="lineno">  122</span>&#160;            <span class="keyword">from</span> Queue <span class="keyword">import</span> Queue</div>
<div class="line"><a name="l00123"></a><span class="lineno">  123</span>&#160;        <span class="keywordflow">except</span> ImportError:  <span class="comment"># Python 3</span></div>
<div class="line"><a name="l00124"></a><span class="lineno">  124</span>&#160;            <span class="keyword">from</span> queue <span class="keyword">import</span> Queue</div>
<div class="line"><a name="l00125"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a32a669fe4cdbb33e9077c9f6683ab3a6">  125</a></span>&#160;        self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a32a669fe4cdbb33e9077c9f6683ab3a6">_queue</a> = Queue(maxconnections)</div>
<div class="line"><a name="l00126"></a><span class="lineno">  126</span>&#160;        <span class="comment"># Establish all database connections (it would be better to</span></div>
<div class="line"><a name="l00127"></a><span class="lineno">  127</span>&#160;        <span class="comment"># only establish a part of them now, and the rest on demand).</span></div>
<div class="line"><a name="l00128"></a><span class="lineno">  128</span>&#160;        <span class="keywordflow">for</span> i <span class="keywordflow">in</span> range(maxconnections):</div>
<div class="line"><a name="l00129"></a><span class="lineno">  129</span>&#160;            self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a9fc3c4e5b5fd6ebe0eb7fc6612941524">cache</a>(PgConnection(*args, **kwargs))</div>
<div class="line"><a name="l00130"></a><span class="lineno">  130</span>&#160; </div>
<div class="line"><a name="l00131"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a9fc3c4e5b5fd6ebe0eb7fc6612941524">  131</a></span>&#160;    <span class="keyword">def </span><a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a9fc3c4e5b5fd6ebe0eb7fc6612941524">cache</a>(self, con):</div>
<div class="line"><a name="l00132"></a><span class="lineno">  132</span>&#160;        <span class="stringliteral">&quot;&quot;&quot;Add or return a connection to the pool.&quot;&quot;&quot;</span></div>
<div class="line"><a name="l00133"></a><span class="lineno">  133</span>&#160;        self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a32a669fe4cdbb33e9077c9f6683ab3a6">_queue</a>.put(con)</div>
<div class="line"><a name="l00134"></a><span class="lineno">  134</span>&#160; </div>
<div class="line"><a name="l00135"></a><span class="lineno"><a class="line" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a6e61f00b011782c3976543e40aecf8f5">  135</a></span>&#160;    <span class="keyword">def </span><a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a6e61f00b011782c3976543e40aecf8f5">connection</a>(self):</div>
<div class="line"><a name="l00136"></a><span class="lineno">  136</span>&#160;        <span class="stringliteral">&quot;&quot;&quot;Get a connection from the pool.&quot;&quot;&quot;</span></div>
<div class="line"><a name="l00137"></a><span class="lineno">  137</span>&#160;        <span class="keywordflow">return</span> <a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html">PooledPgConnection</a>(self, self.<a class="code" href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a32a669fe4cdbb33e9077c9f6683ab3a6">_queue</a>.get())</div>
</div><!-- fragment --></div><!-- contents -->
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection_html"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html">aestate.opera.DBPool.simple_pooled_pg.PooledPgConnection</a></div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00075">simple_pooled_pg.py:75</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection_html_a53256f6e73bf8a755c26c21d9406c7be"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a53256f6e73bf8a755c26c21d9406c7be">aestate.opera.DBPool.simple_pooled_pg.PooledPgConnection._pool</a></div><div class="ttdeci">_pool</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00084">simple_pooled_pg.py:84</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection_html_a58d4f64fbdb7c5c56b498a1c1062154f"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a58d4f64fbdb7c5c56b498a1c1062154f">aestate.opera.DBPool.simple_pooled_pg.PooledPgConnection.__getattr__</a></div><div class="ttdeci">def __getattr__(self, name)</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00094">simple_pooled_pg.py:94</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_html"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html">aestate.opera.DBPool.simple_pooled_pg.PooledPg</a></div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00102">simple_pooled_pg.py:102</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_html_a32a669fe4cdbb33e9077c9f6683ab3a6"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a32a669fe4cdbb33e9077c9f6683ab3a6">aestate.opera.DBPool.simple_pooled_pg.PooledPg._queue</a></div><div class="ttdeci">_queue</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00125">simple_pooled_pg.py:125</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_html_a6e61f00b011782c3976543e40aecf8f5"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a6e61f00b011782c3976543e40aecf8f5">aestate.opera.DBPool.simple_pooled_pg.PooledPg.connection</a></div><div class="ttdeci">def connection(self)</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00135">simple_pooled_pg.py:135</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_html_a9fc3c4e5b5fd6ebe0eb7fc6612941524"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#a9fc3c4e5b5fd6ebe0eb7fc6612941524">aestate.opera.DBPool.simple_pooled_pg.PooledPg.cache</a></div><div class="ttdeci">def cache(self, con)</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00131">simple_pooled_pg.py:131</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection_html_aa6e8fb5dc582c2d9b4243cadcf40f8f8"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#aa6e8fb5dc582c2d9b4243cadcf40f8f8">aestate.opera.DBPool.simple_pooled_pg.PooledPgConnection._con</a></div><div class="ttdeci">_con</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00083">simple_pooled_pg.py:83</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection_html_a1961b0971acfb8564d8f3d65c5ec5bac"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a1961b0971acfb8564d8f3d65c5ec5bac">aestate.opera.DBPool.simple_pooled_pg.PooledPgConnection.close</a></div><div class="ttdeci">def close(self)</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00086">simple_pooled_pg.py:86</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_html_ae03edf57ff55310069135c2e77b19dee"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg.html#ae03edf57ff55310069135c2e77b19dee">aestate.opera.DBPool.simple_pooled_pg.PooledPg.__init__</a></div><div class="ttdeci">def __init__(self, maxconnections, *args, **kwargs)</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00111">simple_pooled_pg.py:111</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection_html_a1dc29b18e0b02d3f4ad84bc543f75d05"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#a1dc29b18e0b02d3f4ad84bc543f75d05">aestate.opera.DBPool.simple_pooled_pg.PooledPgConnection.__init__</a></div><div class="ttdeci">def __init__(self, pool, con)</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00082">simple_pooled_pg.py:82</a></div></div>
<div class="ttc" id="aclassaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection_html_ade325c32687db9b48d41911b9d03d7fd"><div class="ttname"><a href="classaestate_1_1opera_1_1_d_b_pool_1_1simple__pooled__pg_1_1_pooled_pg_connection.html#ade325c32687db9b48d41911b9d03d7fd">aestate.opera.DBPool.simple_pooled_pg.PooledPgConnection.__del__</a></div><div class="ttdeci">def __del__(self)</div><div class="ttdef"><b>Definition:</b> <a href="simple__pooled__pg_8py_source.html#l00098">simple_pooled_pg.py:98</a></div></div>
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